Novel Charge Ordering in the Trimer Iridium Oxide BaIrO3

作者:Terasaki Ichiro*; Ito Shun; Igarashi Taichi; Asai Shinichiro; Taniguchi Hiroki; Okazaki Ryuji; Yasui Yukio; Kobayashi Kensuke; Kumai Reiji; Nakao Hironori; Murakami Youichi
来源:Crystals, 2016, 6(3): 27.
DOI:10.3390/cryst6030027

摘要

We have prepared polycrystalline samples of the trimer Ir oxide BaIrO3 with face-shared Ir3O12 trimers, and have investigated the origin of the phase transition at 182 K by measuring resistivity, thermopower, magnetization and synchrotron X-ray diffraction. We propose a possible electronic model and transition mechanism, starting from a localized electron picture on the basis of the Rietveld refinement. Within this model, BaIrO3 can be basically regarded as a Mott insulator, when the Ir3O12 trimer is identified to one pseudo-atom or one lattice site. The transition can be viewed as a transition from the Mott insulator phase to a kind of charge ordered insulator phase.